Parenthesize all binary expression - fixes #565

Simplifier will deal with ones that weren't needed

Author: GrahamTheCoder

CHANGELOG.md

@@ -9,7 +9,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 
 ### VB -> C#
+
 * Improve multi-declaration field conversion for arrrays - [#559](https://github.com/icsharpcode/CodeConverter/issues/559)
+* Add parentheses around ternary statement - [#565](https://github.com/icsharpcode/CodeConverter/issues/565)
 
 ### C# -> VB
 

CodeConverter/CSharp/VbSyntaxNodeExtensions.cs

@@ -20,20 +20,13 @@ public static ExpressionSyntax ParenthesizeIfPrecedenceCouldChange(this VisualBa
 
         public static bool PrecedenceCouldChange(this VisualBasicSyntaxNode node)
         {
-            bool parentIsSameBinaryKind = node is BinaryExpressionSyntax && node.Parent is BinaryExpressionSyntax parent && parent.Kind() == node.Kind();
+            bool parentIsBinaryExpression = node is BinaryExpressionSyntax;
             bool parentIsReturn = node.Parent is ReturnStatementSyntax;
             bool parentIsLambda = node.Parent is LambdaExpressionSyntax;
             bool parentIsNonArgumentExpression = node.Parent is Microsoft.CodeAnalysis.VisualBasic.Syntax.ExpressionSyntax && !(node.Parent is ArgumentSyntax);
             bool parentIsParenthesis = node.Parent is ParenthesizedExpressionSyntax;
 
-            // Could be a full C# precedence table - this is just a common case
-            bool parentIsAndOr = node.Parent.IsKind(SyntaxKind.AndAlsoExpression, SyntaxKind.OrElseExpression);
-            bool nodeIsRelationalOrEqual = node.IsKind(SyntaxKind.EqualsExpression, SyntaxKind.NotEqualsExpression,
-                SyntaxKind.LessThanExpression, SyntaxKind.LessThanOrEqualExpression,
-                SyntaxKind.GreaterThanExpression, SyntaxKind.GreaterThanOrEqualExpression);
-            bool csharpPrecedenceSame = parentIsAndOr && nodeIsRelationalOrEqual;
-
-            return parentIsNonArgumentExpression && !parentIsSameBinaryKind && !parentIsReturn && !parentIsLambda && !parentIsParenthesis && !csharpPrecedenceSame;
+            return parentIsNonArgumentExpression && !parentIsBinaryExpression && !parentIsReturn && !parentIsLambda && !parentIsParenthesis;
         }
     }
 }

Tests/CSharp/ExpressionTests/ExpressionTests.cs

@@ -995,6 +995,26 @@ private void TestMethod(string str)
 CS0103: The name 'string' does not exist in the current context");
         }
 
+        [Fact]
+        public async Task ConditionalExpressionInStringConcatAsync()
+        {
+            await TestConversionVisualBasicToCSharpAsync(@"Class ConditionalExpressionInStringConcat
+    Private Sub TestMethod(ByVal str As String)
+        Dim appleCount as integer = 42
+        Console.WriteLine(""I have "" & appleCount & If(appleCount = 1, "" apple"", "" apples""))
+    End Sub
+End Class", @"using System;
+
+internal partial class ConditionalExpressionInStringConcat
+{
+    private void TestMethod(string str)
+    {
+        int appleCount = 42;
+        Console.WriteLine(""I have "" + appleCount + (appleCount == 1 ? "" apple"" : "" apples""));
+    }
+}");
+        }
+
         [Fact]
         public async Task ConditionalExpressionInUnaryExpressionAsync()
         {